Keplerian telescope

Table of Contents

Introduction References & Edit History Related Topics

Images

Read Next

Infinite space background with silhouette of telescope. This image elements furnished by NASA.

Telescopes: Seeing Stars

Where Did the Moon Come From?

solar eclipse, sun, moon, astronomy, space

How Do You Tell the Difference Between Total, Annular, Solar, and Lunar Eclipses?

Arrangement of the phases of the moon in total eclipse with Blood Moon

9 Celestial Omens

1 July 2002: The Solar and Heliospheric Observatory (SOHO) satellite reveals a massive solar eruption more than 30 times the Earth's diameter. The eruption formed when a loop of a magnetic field over the surface of the Sun trapped hot gas.

6 Questions About the Sun Answered

Discover

Pluto. The Changing Faces of Pluto. Most detailed view to date of the entire surface of the dwarf planet Pluto, as constructed from multiple NASA Hubble Space Telescope photographs taken from 2002 to 2003.

10 Important Dates in Pluto History

Aphrodite. Greek mythology. Sculpture. Aphrodite is the Greek goddess of love and beauty.

12 Greek Gods and Goddesses

How Is Coffee Decaffeinated?

In this aerial photo, structures are damaged and destroyed October 15, 2005 in Balakot, Pakistan. It is estimated that 90% of the city of Balakot was leveled by the earthquake. The death toll in the 7.6 magnitude earthquake that struck northern Pakistan on October 8, 2005 is believed to be 38,000 with at least 1,300 more dead in Indian Kashmir. SEE CONTENT NOTES.

6 of the World’s Deadliest Natural Disasters

Queen Elizabeth II addresses at opening of Parliament. (Date unknown on photo, but may be 1958, the first time the opening of Parliament was filmed.)

All 119 References in “We Didn’t Start the Fire,” Explained

earthquake. Heavily damaged school in the town of Yingxiu after a major earthquake struck China's Sichuan Province on May 12, 2008.

The 6 Deadliest Earthquakes Since 1950

Mona Lisa, oil on wood panel by Leonardo da Vinci, c. 1503-06; in the Louvre, Paris, France. 77 x 53 cm.

Why Is the Mona Lisa So Famous?

Science & Tech

Keplerian telescope

Written and fact-checked by The Editors of Encyclopaedia Britannica

Article History

Kepler

See all media

Category: Science & Tech

Key People:: Johannes Kepler

Related Topics:: telescope

See all related content →

Keplerian telescope, instrument for viewing distant objects, the basis for the modern refractive telescope, named after the great German astronomer Johannes Kepler. Its eyepiece, or ocular, is a convex (positive, or convergent) lens placed in back of the focus, the point at which the parallel light rays converge; and the instrument produces an inverted (“real”) image that can be projected or made visible. An additional convergent lens is provided between the objective and the eyepiece to right the image. The instrument needs to be rather long because of the intermediate inversion of the image, and the tube is often constructed to be collapsible.

This article was most recently revised and updated by Amy Tikkanen.